Antenna design for a mobile computing device is an important consideration and is often limited by strict performance constraints. For a mobile computing device with a small form factor, an internal antenna may be located very close to a removable battery. In some cases, there is not enough distance between the battery and the antenna to isolate mutual coupling. Such coupling could introduce an additional inductor and/or capacitor resulting in reduced antenna performance.
To ensure desired performance of a mobile computing device, the design of each antenna may be optimized for use with a standard battery. If the antenna design is optimized for a standard battery, however, performance may be degraded when the mobile computing device is attached to an accessory such as an extended battery used instead of the standard battery. Accordingly, there exists the need for improved antenna designs for achieving desired performance when using an attached accessory.